Do wood chips deplete soil nutrients?

Wood chips will have a temporary impact on the nitrogen levels near the soil surface, but will not affect the roots that are deeper in the soil. When fresh chips are added to the soil, the decomposition of the carbon-rich wood causes microbes to extract nitrogen from the surface layers of the soil, using that nitrogen to decompose the wood over time. This temporary nitrogen tie-up will only affect the top half-inch of soil and will last 4 to 6 weeks.

The effects of nitrogen remain near the soil's surface. The roots of plants under this depth will not be affected at all. I have been using fresh wood chips surrounding established trees for years without any nutrient disturbance. Aged wood chips do not produce this minor temporary effect at all. Proper application of wood chips is a safe practice.

Proper utilization of wood chips should prevent them from causing trouble. Ensure that you apply the chips at least 6 inches away from tree trunks and plant stems. Donut-shaped mulch rings can be created around the plant to protect it from the elements. This reduces moisture retention against the bark. Use 3-4 inch layers for best weed suppression without compaction.

Wood chips offer numerous benefits beyond the short-term nitrogen issue. They moderate soil temperature all year. They greatly increase earthworm populations. They suppress weeds. Once the leaching phase is complete, it actually enhances long-term soil fertility.

Read the full article: Top 10 Best Mulch for Gardens: Ultimate Guide